Announcement

Collapse
No announcement yet.

Why don't I ever see these....?

Collapse
X
 
  • Filter
  • Time
  • Show
Clear All
new posts

  • Face
    replied
    Re: Why don't I ever see these....?

    Originally posted by dthomas View Post
    I would say it is a ground loop but probably not external to your equipment. I suspect either the Crown or the Marantz have a significant difference in where they sit in relation to 0V or ground. Question is does one have an issue or is it inherent to their design. The only other issue would be that you have an RFI issue which should be present on balanced or unbalanced connections.

    This assumes you have tested all your cables etc... which I figure you have.
    Cables are fine, they(Mogami Gold) were dead silent in my other rig. It could be possible there is still some sort of ground issue, I may run a cable between the Marantz, Crown, and conditioners cases. This may have been non issue if it weren't for me installing much more sensitive speakers recently...

    Originally posted by ReissM View Post
    I get a lot of noise coming in through the "cable-TV" coax cable. When I connect it to my stereo it creates the same problem that you're describing. Try this: unplug the coax cable that feeds the cable TV signal into your HT system. Does all the noise suddenly disappear? If yes, your have two options: float the third wire, ground connection on your power cable. Or buy a transformer that isolates the signal (and noise) coming from the cable-TV coax cable.
    I'll give this a whirl, but don't have my hopes up as there's a fiber optic run to the house. Unless the optical/coax converter box in the garage, which is on it's own line also, is creating a loop. I had a high bandwidth coax isolation transformer in series when I had cable, but removed it when I upgraded to FIOS. Now that I've installed much more sensitive speakers(94db opposed to 85ish), maybe it was there all along, but not very noticeable.
    Originally posted by fwiler View Post
    I have the Crown XLS 1000 and 1500, both used for subs.
    I can't hear a thing from them and I'm very sensitive to fan noise.

    The only thing I don't like is there is no trigger to power on.
    I might try one of those Belkin power strips that trigger based on another device turning on in the power strip.
    The XLS amps are known to be quieter than the XTi.

    Leave a comment:


  • fwiler
    replied
    Re: Why don't I ever see these....?

    I have the Crown XLS 1000 and 1500, both used for subs.
    I can't hear a thing from them and I'm very sensitive to fan noise.

    The only thing I don't like is there is no trigger to power on.
    I might try one of those Belkin power strips that trigger based on another device turning on in the power strip.

    Leave a comment:


  • dthomas
    replied
    Re: Why don't I ever see these....?

    Originally posted by ReissM View Post
    I get a lot of noise coming in through the "cable-TV" coax cable. When I connect it to my stereo it creates the same problem that you're describing. Try this: unplug the coax cable that feeds the cable TV signal into your HT system. Does all the noise suddenly disappear? If yes, your have two options: float the third wire, ground connection on your power cable. Or buy a transformer that isolates the signal (and noise) coming from the cable-TV coax cable.
    Good point I had a similar issue with a DirecTV box and solved it using an optical cable instead of an analog connection but this was in a 2 channel set up. I now have all digital audio signals until my final amp with the exception of the subwoofer outputs. A bit ironic that is balanced outputs create more noise than his unbalanced outputs.

    Leave a comment:


  • ReissM
    replied
    Re: Why don't I ever see these....?

    Originally posted by Face View Post
    Another gripe. When using this amp in my HT rig, hooked up to the balanced outputs of a Marantz processor, the noise floor jumps up significantly when the Crown is powered on. There is high pitched buzz and also a hum through my speakers and subs. When used on the LFE out it's not as bad, but when connected to the L&R out it's a real issue. I doubt it's a ground loop as everything is on the same dedicated outlet and power conditioner, and without the power conditioner it's even worse.
    I get a lot of noise coming in through the "cable-TV" coax cable. When I connect it to my stereo it creates the same problem that you're describing. Try this: unplug the coax cable that feeds the cable TV signal into your HT system. Does all the noise suddenly disappear? If yes, your have two options: float the third wire, ground connection on your power cable. Or buy a transformer that isolates the signal (and noise) coming from the cable-TV coax cable.

    Leave a comment:


  • dthomas
    replied
    Re: Why don't I ever see these....?

    Originally posted by Face View Post
    Another gripe. When using this amp in my HT rig, hooked up to the balanced outputs of a Marantz processor, the noise floor jumps up significantly when the Crown is powered on. There is high pitched buzz and also a hum through my speakers and subs. When used on the LFE out it's not as bad, but when connected to the L&R out it's a real issue. I doubt it's a ground loop as everything is on the same dedicated outlet and power conditioner, and without the power conditioner it's even worse.

    I would say it is a ground loop but probably not external to your equipment. I suspect either the Crown or the Marantz have a significant difference in where they sit in relation to 0V or ground. Question is does one have an issue or is it inherent to their design. The only other issue would be that you have an RFI issue which should be present on balanced or unbalanced connections.

    This assumes you have tested all your cables etc... which I figure you have.

    Leave a comment:


  • Face
    replied
    Re: Why don't I ever see these....?

    Another gripe. When using this amp in my HT rig, hooked up to the balanced outputs of a Marantz processor, the noise floor jumps up significantly when the Crown is powered on. There is high pitched buzz and also a hum through my speakers and subs. When used on the LFE out it's not as bad, but when connected to the L&R out it's a real issue. I doubt it's a ground loop as everything is on the same dedicated outlet and power conditioner, and without the power conditioner it's even worse.

    Leave a comment:


  • Face
    replied
    Re: Why don't I ever see these....?

    Originally posted by Face View Post
    I use Noctua fans throughout my PC builds, I'll give one a try in the XTi.
    I should have used an SPL meter to see what sort of change, if any, the Noctua fan made. The amp is still loud, just not as bad. The real test will be when it's placed in a rack and with music or a movie playing. Finally gave it's software a try too, it's not bad, but not great either. And I miss the phase adjustment knob from a dedicated sub amp. I know I can swap the polarity if need be, but for fine adjustments...

    Leave a comment:


  • Face
    replied
    Re: Why don't I ever see these....?

    Originally posted by Whitneyville1 View Post
    If any amp fans are noisy, check with Newegg, Tiger Direct or a computer "geek" shop for the new "silent" fans (also known as "shark tooth fans" because of the blades), they move more CFM and are so quiet you keep checking to see if they're running
    I use Noctua fans throughout my PC builds, I'll give one a try in the XTi.

    Leave a comment:


  • Silver1omo
    replied
    Re: Why don't I ever see these....?

    Originally posted by mppatt01 View Post
    How are those of you using these amps for subs powering them on and off? Leave them on always, with a triggered relay, or manually (gasp!)
    Manually, the amp is in the same "rack" where I keep the remote controllers.

    Leave a comment:


  • dthomas
    replied
    Re: Why don't I ever see these....?

    http://www.amazon.com/XANTECH-AC1-Co...pd_sim_sbs_e_1

    This works if you amp doesn't have a 12V dc trigger output use a 12V wall wart and plug it into the switched outlet on the back of the HT Receiver and use it to trigger the AC outlet.

    If you have handy just get a 15A solid state relay rated for 240VAC, they usually trigger from 3 to about 24VDC you will need an ac outlet and a project box. Basically the same thing as the one in the link except you DIY it.

    Leave a comment:


  • Jonathan Anspach
    replied
    Re: Why don't I ever see these....?

    Originally posted by mppatt01 View Post
    How are those of you using these amps for subs powering them on and off? Leave them on always, with a triggered relay, or manually (gasp!)
    I use one of these, but it's a pricey solution.

    http://www.furmansound.com/product.p...01&id=PS-8R_II

    Leave a comment:


  • mppatt01
    replied
    Re: Why don't I ever see these....?

    How are those of you using these amps for subs powering them on and off? Leave them on always, with a triggered relay, or manually (gasp!)

    Leave a comment:


  • dthomas
    replied
    Re: Why don't I ever see these....?

    Originally posted by Wolf View Post
    I've not had that experience at all, Dave. I use the XLS1500, running balanced XLR, and I don't hear any noise issues, but the 1500+ have a lower SNR than the 1000 does. As to Pete's note on usage, I know the fan runs, but even when it's on I have to go behind the unit or place my ear right on the front panel for it to become audible using it as a main stereo amp.
    It could be that the associated equipment is not up to par and is passing noise through, but my Anthem/Crown combo appears to me to be dead quiet..

    Killa- looks aside, these are great for the money.

    Later,
    Wolf
    First I was speaking in regard to the OP's comments on the XLS 1000. It is good to hear the 1500 may be better suited for HiFi duty. The unit I heard (an XLS1000) you could clearly hear the fans running in soft passages in a recording. I was seated about 8 feet away. But do take that for what it is just my opinion. My experience might not be typical maybe his had a very noisy fan but it was only a few weeks old. Just a word of caution and my luck with fan cooled amps is the fans only get louder as the amps get older. Lot of good convection cooled amps in this price range.

    Leave a comment:


  • Pete Schumacher
    replied
    Re: Why don't I ever see these....?

    Originally posted by Face View Post
    Pete, how would a the demand go up for a sub compared to a full range speaker? Regardless, I had the fans screaming on a pair of full range speakers last night and need to look into fan mods or another solution.
    It has to do with peak to average ratio.

    When you run a full range music signal into an amp (20Hz - 20KHz) the amp will need to hit peak power that will be at least 5 times the average power, 10 times and higher if the recording is excellent. If the amp is 1000W, that means if you're going to be driving a speaker with unclipped peaks, you will deliver about 100W RMS when the signal has a 10:1 peak to average ratio.

    If you limit the bandwidth, the peak to average ratio goes way down. That means your 1000W amp can now deliver maybe 250 - 500W RMS during program material without clipping on the peaks. Higher average output would mean higher heat dissipation.

    Leave a comment:


  • Wolf
    replied
    Re: Why don't I ever see these....?

    I don't notice the fan running in my XLS1500 at all running full-range mains. It may very well be a different series of product issue.

    Yes- subs are usually less sensitive, and require more juice, therefore, more heat generation. That's how I saw it.

    Later,
    Wolf

    Leave a comment:

Working...
X